It could be not normally an issue with new gaskets unless it has warped some how. If this is not his first rodeo, as stated then he should know what was done or not done. Can he test circuits as well or limited in that department. - ProfessorG
got the sluggish part fixed but it still jerks hard when you let off of the gas pedal or push it down. Could this be caused by the air mass system? we have checked everything else out and it runs great, just jerky - JLDB
They are in proper position and are not messed up at all. Not even a little loose. Is it possible that the air mass sensor could cause this? It's just a little plastic piece in the air mass hose.
I wouldn't think it would be the cause of it jerking when you let off the accelerator. Did you try to watch the engine while someone holds the brake pedal and put it in gear and give it gas in drive and reverse watching to see the movement of the engine to see how far it moves or when reving the engine in gear and let off the gas to see if it falls back. Of course the brake pedal is being held at all times. - ProfessorG